Additional investigations of pharmacodynamic biomarkers conducted in Step 2 — including NK cell activity before the first study treatment and tumor expression levels of EPHA2, CD16, NKp46/NCRI, CD3, CD68, PD-L1, E-cadherin, EGFR, and HER2 — yielded no apparent trends of correlation between baseline level or on-treatment changes of these biomarkers and best overall response or disease control ratio. Here, ERBB2 is linked to neoplasm.